13318221 has 32 divisors (see below), whose sum is σ = 22118400. Its totient is φ = 6955200.

The previous prime is 13318213. The next prime is 13318223. The reversal of 13318221 is 12281331.

13318221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 13318221 - 2³ = 13318213 is a prime.

It is a super-3 number, since 3×13318221³ (a number of 22 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13318223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10996 + ... + 12146.

It is an arithmetic number, because the mean of its divisors is an integer number (691200).

Almost surely, 2^13318221 is an apocalyptic number.

It is an amenable number.

13318221 is a deficient number, since it is larger than the sum of its proper divisors (8800179).

13318221 is a wasteful number, since it uses less digits than its factorization.

13318221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1209.

The product of its digits is 288, while the sum is 21.

The square root of 13318221 is about 3649.4137885419. The cubic root of 13318221 is about 237.0365981687.

Adding to 13318221 its reverse (12281331), we get a palindrome (25599552).

The spelling of 13318221 in words is "thirteen million, three hundred eighteen thousand, two hundred twenty-one".